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radiation is performed, and it is shown that it corresponds to the displacement of the

surface of the object under the action of surface acoustic wave (SAW). The value of

the optical beam spot width on the surface of the control object is also analyzed for

the effectiveness of the proposed method. It has been experimentally shown that its

width should be relatively greater than 3Λ, and Λ is the length of the SAW. Also

considered are limitations on the magnitude of optical beam expansion that can be

used effectively in this technique. Based on the analysis of the optical field, I also the

width of the spot of the optical beam shows that the proposed method can be applied

in the frequency range 1 - 15 MHz. Techniques for determining the speed of the

SAW by the extended beam method, which does not move the photodetector, are

offered, which makes it possible to simplify the measurements and to avoid errors in

determining the position of the photodetector.

A new simple technique for stabilizing the operation of the Michelson

interferometer under vibration and temperature drift is proposed. Stabilization of the

interferometer is achieved due to the formation of the interference pattern in the form

of parallel interference bands on the surface of the photodetector. A numerical

simulation of the proposed stabilization scheme is performed and it is shown that the

most effective geometry is the width of the interference line being equal to the length

of the SAW mapping to the plane of the sensitive area of the photodetector. An

experimental study of the proposed stabilization scheme showed its effectiveness in

the case when the optical beam radius exceeds several SAW lengths.

Methods for reducing the inaccuracy of the SAW rate of a piezoelectric

transducer have been developed in which the excitation and recording prisms are

rigidly connected. The influence of the temperature change of the converter on the

error of measuring the velocity of the SAW is analyzed. A method of minimizing the

temperature error of speed measurement by compensating for the temperature change

of linear dimensions by the temperature change of the velocity of the acoustic waves

of the transducer elements is proposed. The effect of the depth on the transducer

surface on the measurement of the SAW rate is also considered for the first time. It is